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Is catch-per-unit-effort proportional to abundance?

2001· article· en· 610 citations· W2122264634 on OpenAlex· 10.1139/f01-112

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Canadian funderA Canadian agency funded it. The work may carry no Canadian affiliation at all.
Canadian venueIt was published in a Canadian venue.

No Canadian affiliation. An affiliation-only frame — the usual design — would never have seen this work. It is one of the works that make the case for inverting the frame.

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Opus teacher head0.023
GPT teacher head0.235
Teacher spread
0.212 · how far apart the two teachers sit on this one work
Validation status
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Abstract

We compiled 297 series of catch-per-unit-effort (CPUE) and independent abundance data (as estimated by research trawl surveys) and used observation error and random effects models to test the hypothesis that CPUE is proportional to true abundance. We used a power curve, for which we were interested in the shape parameter (β). There was little difference among species, ages, or gear types in the distributions of the raw estimates of β for each CPUE series. We examined three groups: cod, flatfish, and gadiformes, finding strong evidence that CPUE was most likely to remain high while abundance declines (i.e., hyperstability, where β < 1). The range in the mean of the random effects distribution for β was quite small, 0.64–0.75. Cod showed the least hyperstability, but still, 76% of the mass of the random effects distribution was below 1. Based on simulations, our estimates of β are positively biased by approximately 10%; this should be considered in the application of our findings here. We also considered the precision of CPUE indices through a meta-analysis of observation error variances. The most precise indices were those from flatfish (median coefficient of variation of [Formula: see text]0.42).

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The record

Venue
Canadian Journal of Fisheries and Aquatic Sciences
Topic
Fish Ecology and Management Studies
Field
Environmental Science
Canadian institutions
Funders
Natural Sciences and Engineering Research Council of CanadaKillam Trusts
Keywords
Catch per unit effortStatisticsMathematicsRange (aeronautics)Abundance (ecology)Series (stratigraphy)FisheryEconometricsBiology
Has abstract in OpenAlex
yes